Cat scratching

My cat, Charley, wears soft claws, and that prevents him from damaging
all the furniture in my house except for one sofa with rather soft
fabric. To get attention, he "chooses" to scratch this sofa and of
course, it works every time! ;-) I go over and shoo him away or try
to distract with play.

Anyway, I came across a scratching post on the internet that
automatically delivered a treat when the cat used the post. Since
Charley enjoys treats, I'm thinking this might be the thing to keep
him from my soft sofa. I kick myself for not buying it when I found
it, but now I can't find it. Is anyone familiar with this product?

Thanks!
Michelle